The present invention relates to a process for preparing cycloalkanols and cycloalkanones by the liquid phase oxidation of a cycloalkane, having from 5 to 12 carbon atoms in the ring, by means of a gas containing molecular oxygen. The oxidation mixture thus obtained, containing cycloalkyl hydroperoxide, is subsequently treated with a cycloalkyl hydroperoxide-decomposing salt in the presence of an aqueous solution of an alkali metal hydroxide to form cycloalkanols and cycloalkanones. A process of this type is known from British Patent Specification No. 1,382,849.
In this known process, the oxidation mixture containing the cycloalkyl hydroperoxide is treated with the alkaline solution simultaneously with, or subsequent to, the addition of the cycloalkyl hydroperoxide-decomposing metal salt, while the aqueous phase portion of the resulting reaction mixture is maintained at a pH of between 8 and 13, measured at 25.degree. C. This process, however, has the disadvantage that the yield of cycloalkanols and cycloalkanones, based on the cycloalkane converted, is relatively low. Applicant has found that this yield can be enhanced by maintaining the aqueous phase portion of the reaction mixture at an extremely high pH, for instance corresponding with 0.5 N of free sodium hydroxide or more. However this requires a very high consumption of alkali, which in turn renders such a process economically unattractive.
It is therefore an object of this invention to provide an economically attractive process for the preparation of cycloalkanols and cycloalkanones having an increased yield as compared to the prior art processes. It is a further object of this invention to provide a process having increased yield of cycloalkanols and cycloalkanones, while at the same time minimizing the consumption of alkali.